An engine has 8 cylinders and crankshaft supported by 5 bearings of dimensions(adsbygoogle = window.adsbygoogle || []).push({});

Journal diameter = 120mm, Axial length = 114mm, Radiall clearance =0.06mm and Oil density = 890.0kgm^-3.

If the engine runs at 900rpm and is lubricated with oil whose kinematic viscosity is 180cSt at cold and 38cSt whem warm, using Petrov's equation determine the shear drag torque required to turn the crankshaft in its main bearings when cold and and warm and what would be the power at these conditions be?

Also, if the engine has run for an hour determine the heat generated by all the main bearings?

If all this heat could be turned into kinetic energy, determine how fast a 1tonne car would be going if it had this energy, and how high the car could be lifted using this energy.

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# Using Petrov's equation to determine the shear drag torque in a motor

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